Today in World War II History—June 28, 1943 POSTED: Thursday, June 28, 2018 by Sarah Sundin Avro Lancaster bombers of RAF No.44 Squadron, 1942 (Imperial War Museum: TR 197) 75 Years Ago—June 28, 1943: Royal Air Force bombs Cologne, Germany, heavily damaging the cathedral and ending the Battle of the Ruhr—total of 872 British bombers lost.